At the end of the Twentieth Century, the frequency of silver (gray) labs began to increase in North America due to an increase in the number of chocolate labs in the gene pool of Labrador Retrievers. These Silver Labs in turn fueled an enormous controversy within the Labrador community. 
Fortunately, by the advent of the Twenty-First Century, the controversy surrounding Silver Labs subsided except for a few remaining  breeders of  "standard" colors. These remaining opponents of Silver Labs are the K-9 version  of the "Flat Earth Society". Unfortunately, those holdout breeders who refuse to acknowledge AKC's acceptance of silver labs, continue to confuse the general public by making unfounded accusations about the purity of the Silver Labs breeding. In an attempt to quiet the ranting of the more vocal opponents of Silver Labs, one breeder of silvers offered a $100,000.00 Silver Lab Challenge to any of these "experts" who wished to put their money where their mouth was concerning their accusations surrounding the ancestry of silver labs. And to the man, not one of those "experts" you see on the Internet was willing to stand behind their Flat Earth accusations regarding Silver Labs.  DNA testing and mapping of silver labs was done during the close of the Twentieth Century and meticulous investigation of each silver labs ancestry was conducted by investigators from AKC. All conclusions were the same, i.e., "there was no reason to doubt that the dogs were purebred Labrador Retrievers," (see conclusion issued by AKC). Amazingly, the Flat Earth Opponents of Silver Labs counter these scientific conclusions with the incredibly insane accusation that the "cross-breeding" which allegedly produced the Silver Labs was either covered up by line breeding or happened to long ago to be detected by DNA testing. If anyone ever needed an indication of just how ignorant opponents of Silver Labs are, this statement should be the key. Every K-9 carries in its genes a complete history of its ancestors going all the way back to wolves.
Silver Labs are pure bred Labrador Retrievers and their ancestry is beyond reproach. Fortunately, kennel clubs around the world do not have the political pressure from mercenary American breeders of  "normal" colored labs and already accept silver labs without all the political fuss and pressure being applied to AKC (the original standard for a lab has always been "a coat of a solid color"). If a person should come upon one of the remaining "Silver Lab Hate sites" on the net and develops ANY doubts about Silver Labs, that person should go directly to AKC and ask the pertinent question to learn the facts.
The silver coat color in Labradors has gained much attention recently and is a very controversial topic
 (see The Labrador Coat Color Controversy: Do Silver Labs Really Exist?). Reasons for the controversy stem from the
 lack of information available to trace the origins of this color in the breed as well as the fact that the AKC standard for
the Labrador breed does not acknowledge silver as an acceptable color for a Lab. Some breed enthusiasts consider
the silver coloration to be a sign of impurity of the bloodline, however, what geneticists have come to understand of
recessive alleles is that they may be passed through many generations going undetected. There are silver labs surfacing now here, there, in countries that don't have any records of silver labs....which is further proof that Silver labs are 100% Labrador.

"To err is Human, to forgive, is canine"-unknown